1. Identifying Variables

2. There are 3 types of Variables 1. Independent (aka manipulated) 2
There are 3 types of Variables 1. Independent (aka manipulated) 2. Dependent (aka responding) 3. Controlled (constants)

3. 3 Kinds of Variables Independent Variable Manipulated Variable
something that is purposefully changed by the investigator
What is tested
What is manipulated

4. 3 Kinds of Variables Dependent Variable Responding Variables
something that might be affected by the change in the independent variable
What is observed
What is measured
The data collected during the investigation

5. 3 Kinds of Variables
Controlled Variable – a variable that is not changed
Also called constants
Allows for a “fair test”
Allows for a controlled experiment

6. Variables and the Hypothesis Statement
Use an: If, & Then statement.
If the independent variable changes, then the dependent variable will change.

7. DRY*MIX D – Dependent Variable R – Responding Variable
Y – Y-axis of a graph *
M – Manipulated Variable
I – Independent Variable
X – X-axis of a graph

8. For Example:

9. Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle.
Independent Variable:
Dependent Variable:
Control:

10. Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle.
Independent Variable: Students
Dependent Variable: Time for puzzle
construction
Control: Puzzle

11. A study was done to see if different composition of skateboard wheels affected the performance of the board. The same board, the same rider and the same course were used. Only the wheels were different.
Independent Variable:
Dependent Variable:
Control

12. A study was done to see if different composition of skateboard wheels affected the performance of the board. The same board, the same rider and the same course were used. Only the wheels were different.
Dependent Variable: Skateboard Performance
Independent Variable: Wheels
Control: Skateboard, Rider, Course

13. Groups of students were given different types of paper to construct paper airplanes. They all use the same pattern for their planes. The planes were tested to see which ones would fly the greatest distance.
Manipulated Variable:
Responding Variable:
Control:

14. Groups of students were given different types of paper to construct paper airplanes. They all use the same pattern for their planes. The planes were tested to see which ones would fly the greatest distance.
Independent Variable: Paper
Dependent Variable: Distance plane flies
Control: Airplane pattern

15. An experiment was done to see which colored sand would heat up the most when placed in the sun. The sand samples were white, red, green and black. All samples were the same amount, placed in identical containers, left in the sun the same amount of time and the temperature was measured with the same thermometer. Independent Variable: Dependent Variable: Control:

16. An experiment was done to see which colored sand would heat up the most when placed in the sun. The sand samples were white, red, green and black. All samples were the same amount, placed in identical containers, left in the sun the same amount of time and the temperature was measured with the same thermometer. Independent Variable: Sand Color Dependent Variable: Sand Temperature Control: Sand amount, container & thermometer